DEVELOPMENT TRENDS g


keyhole during welding, thus opening new possibilities in increasing process quality, speed, and creating new applications entirely. With the technology still being relatively new, however, industry is currently looking to fully understand its benefits. Bosch Research, for example, is conducting research to determine the relationship between different beam shapes and other parameters such as laser power, weld depth, material type, and so on. It is looking to identify which shapes can be used, for example, to influence welding speeds in certain materials without inducing additional defects such as pores or cracking.


AI optimises process monitoring In recent years AI, like it has with many other aspects of modern life, has found its way into laser materials processing. More specifically, the technology has been shown to have benefits in process monitoring, where well-trained algorithms can analyse sensor signals and detect system deviations, errors and defects faster and more reliably than classic monitoring and control systems. The technology is being applied across all aspects of laser processing, from cutting and welding to additive manufacturing and cleaning. For example, the DIPOOL project (digital


process online optimiser for intelligent laser machines), currently underway by four industrial companies and two research institutes, is integrating AI and machine learning (ML) into laser cutting and welding. The project seeks to address the issue that while many SMEs can now afford lasers, they often lack the capacity and know- how to optimally fine tune them, especially when applications change frequently. The partners are therefore developing capabilities for the automatic and robust monitoring, quality assurance and optimisation of laser machines for changing manufacturing tasks. They estimate that the integration of AI and ML into laser cutting and welding systems will increase their overall efficiency by approximately 25%. Such systems will also be accessible to SMEs, due to the prices of laser and computing power both having fallen significantly in recent years.


Lasers target hydrogen fuel cell production Lasers continue to see widespread adoption across the field of e-mobility, a trend only set to increase further due to advancements such as those covered in this article – blue/green lasers, dynamic beam shaping, AI-powered process monitoring. The technology has proven itself to be the perfect tool for electric vehicle battery production, for example, where it has more


than 30 applications such as welding copper battery tabs and busbars. It can also be used to weld pairs of copper hairpins together for electric motors. Trumpf in particular has seen success in the field, with e-mobility currently making up around 40% of the revenue of its laser division. In addition to battery and electric motor manufacturing, the firm has also set its sights on the fabrication of bipolar plates for hydrogen fuel cells, which it see’s capturing an approximate 10 to 20% share of the e-mobility market. Each bipolar plate is approximately the


size of an A4 sheet of paper and is not much thicker than a human hair. A fuel stack features 300 to 500 plates welded together, requiring hundreds of thin seams to be made, each anywhere from 3 to 5m in length and being barely visible to the naked eye. At a weld speed of 1m/s this would result in a single stack taking up to around 40 minutes to weld, with a medium-size car requiring one fuel cell stack and heavier vehicles requiring more. Each weld seam also needs to be absolutely gas-tight and perfect, with even the smallest error potentially being fatal. The welds must be made over complex geometries over a very large area with tremendous accuracy. In addition, stack manufacturers must keep the heat entering


“Ultrafast lasers have now reached a stage where they can achieve processing throughputs that are useful in industry”


the workpiece to a minimum in order to prevent the metal sheets from warping. This stringent list of requirements rules out almost all the available joining processes – apart from laser welding. Trumpf is therefore currently working with leading firms in fuel cell production to develop additional laser techniques and integrated sensor solutions in order to make fuel cell manufacturing more efficient and cost-effective in the future. Meanwhile, Civan lasers has also targeted


fuel cell production as an application of the rapid parameter-altering capabilities of its new Dynamic Beam Lasers. By monitoring welds in real time and analysing them, for example, with the assistance of AI, it could be possible to observe defects happening in real time and then adjust the laser’s beam shape, frequency, and power to ensure a perfect weld is achieved.


8 LASER SYSTEMS EUROPE THE 2023 GUIDE TO LASER SYSTEMS


3D printers are now using multiple lasers to achieve extremely high build rates, such as SLM Solutions’ NXG XII 600E, which uses 12 1kW lasers to offer build rates of up to 1,000cm3


/hr


Ultrafast lasers reach high throughput Ultrafast lasers have now reached a stage where they can achieve processing throughputs that are useful in industry. This is thanks to both the technology reaching average powers in the kilowatt regime, as well as the development of innovative beam delivery solutions that enable that increased power to be wielded over larger areas. For example, the multi-year LAMpAS


project has now successfully developed a new machine for the high-throughput (in the order of m2/min), low-cost production of laser-textured functionalised surfaces with controlled length scales and feature sizes. The machine consists of: a 1.5kW


ultrafast laser source from Trumpf offering 1-3ps pulse durations and pulse energies up to 4mJ; a unique optical head that combines a specially designed polygon scanner from Scanlab with a DLIP unit from TU Dresden, which can produce periodic surface structures with features of around 3.5µm in size; and two real-time process monitoring systems that assure the stability of the structuring process and the quality of the obtained surface properties. The new system will significantly increase the deployability, flexibility and efficiency of direct laser interference patterning (DLIP) at industrial levels, for producing nature-inspired periodic structures with hydrophobic, anti-fingerprint, decorative, and easy-to-clean properties. Such structures could be applied as surface finishes for ovens, fridges, and other home appliances. l


@LASERSYSTEMSMAG | WWW.LASERSYSTEMSEUROPE.COM


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74